{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-47138: Parse Server: Pre-authentication denial of service via client version header regex backtracking","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-47138","status":"final","version":"1","initial_release_date":"2026-06-12T18:22:02.751Z","current_release_date":"2026-06-12T18:56:14.419Z","revision_history":[{"date":"2026-06-12T18:22:02.751Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.77 and 9.9.1-alpha.1, an unauthenticated attacker who knows a publicly-known Parse Application ID can submit a single HTTP request whose client SDK version field contains adversarial input that triggers polynomial backtracking in a request-header parser. The parsing runs before session authentication and before rate limiting on every /parse/* request, so the request consumes seconds to minutes of synchronous CPU on a Node.js worker before any access control evaluates it. A small number of concurrent requests can saturate a worker; a single large request via the body-field variant can pin a worker for minutes. Production deployments running the default configuration are affected. This issue has been patched in versions 8.6.77 and 9.9.1-alpha.1.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-47138 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-47138"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-47138"},{"category":"external","summary":"https://github.com/parse-community/parse-server/security/advisories/GHSA-38m6-82c8-4xfm","url":"https://github.com/parse-community/parse-server/security/advisories/GHSA-38m6-82c8-4xfm"},{"category":"external","summary":"https://github.com/parse-community/parse-server/pull/10463","url":"https://github.com/parse-community/parse-server/pull/10463"},{"category":"external","summary":"https://github.com/parse-community/parse-server/pull/10464","url":"https://github.com/parse-community/parse-server/pull/10464"}]},"product_tree":{"branches":[{"category":"vendor","name":"parse-community","branches":[{"category":"product_name","name":"parse-server","branches":[{"category":"product_version","name":"< 8.6.77","product":{"name":"parse-community parse-server < 8.6.77","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:parse-community:parse-server:*:*:*:*:*:*:*:*"}}},{"category":"product_version","name":">= 9.0.0, < 9.9.1-alpha.1","product":{"name":"parse-community parse-server >= 9.0.0, < 9.9.1-alpha.1","product_id":"CSAFPID-2","product_identification_helper":{"cpe":"cpe:2.3:a:parse-community:parse-server:*:*:*:*:*:*:*:*"}}}]}]}]},"vulnerabilities":[{"cve":"CVE-2026-47138","title":"Parse Server: Pre-authentication denial of service via client version header regex backtracking","notes":[{"category":"description","text":"Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.77 and 9.9.1-alpha.1, an unauthenticated attacker who knows a publicly-known Parse Application ID can submit a single HTTP request whose client SDK version field contains adversarial input that triggers polynomial backtracking in a request-header parser. The parsing runs before session authentication and before rate limiting on every /parse/* request, so the request consumes seconds to minutes of synchronous CPU on a Node.js worker before any access control evaluates it. A small number of concurrent requests can saturate a worker; a single large request via the body-field variant can pin a worker for minutes. Production deployments running the default configuration are affected. This issue has been patched in versions 8.6.77 and 9.9.1-alpha.1.","title":"CVE description"}],"product_status":{"known_affected":["CSAFPID-1","CSAFPID-2"]},"scores":[{"cvss_v4":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","baseScore":8.7,"baseSeverity":"HIGH"},"products":["CSAFPID-1","CSAFPID-2"]}],"remediations":[{"category":"none_available","details":"No fixed version is published yet. Monitor the upstream advisory.","product_ids":["CSAFPID-1","CSAFPID-2"]}]}]}